When a source node sends packets to a destination node in a communications network, packets may be stored in an input buffer of a network component where the packets may be retrieved and may be processed by the destination node. If a source node transmits packets to a destination node faster than the destination node can process the packets, congestion at the destination node may occur as traffic in its input buffer builds up. Therefore, flow control may be applied to control the traffic from the source node to the destination node.
An example of a flow control scheme is described in the IEEE (Institute of Electrical and Electronics Engineers, Inc.) 802.3 specification, IEEE Std. 802.3, 2002 Edition, current edition published on Mar. 8, 2002. Under the Ethernet flow control scheme, when a destination node becomes congested, the destination node may send a flow control pause frame to the source node. The flow control pause frame may signal the source node to stop all traffic to the destination node. In some cases, however, this may not be desirable.